Study On Sulfidation Performance Of Zn/Mn/Cu-Based Sorbent Supported On Semi-Coke In Medium Temperature Coal Gas

Medium temperature desulfurization occupies an important position in clean and efficiency poly-generation technology based on gasification gas and pyrolysis gas. The fine desulfurization is paid the more attention due to the environmental protection and the requirement technology related higher precision of desulfurization. So,it is necessary to prepare and study on the sorbent with good stability of circulation and high precision.Semi-coke has the similar pore structure to activated carbon, and is cheapper and easier to obtain. So it is chosen as sorbent carrier through experiment selection. ZnO is selected as the main active component of desulfurizer with highest precision . But Zn-based desulfurizer has small sulfur capacity and slowly reaction rate, so MnO is selected as a secondary active ingredients to improve the sulfur capacity and reaction rate, and CuO with good heat stability is another secondary active ingredients for improving mechanical properties of sorbent.The pore structure of semi-coke was improved by high-pressure impregnation method. The upload amount of active components was controlled by changing the concentration of dipping solution,. The procedures of the sorbent preparation include high-pressure hydrothermal synthesis, filtration, drying, calcining. The sulfidation experiment was carried in the atmospheric-pressure fixed-bed reactor and feeding gas was composed of CO(33 vol%), H2(39 vol%), H2S(300±10 ppm) and N2(balance) in the temperature range of 300 oC ~ 550 oC. The samples were analysed by the measure of SEM, XRD and BET techniques.The experimental results were listed as below:1)Zn/Mn/Cu-based sorbent supported in semi-coke can be prepared by high-pressure impregnation method and has excellent desulfurization performance in medium temperature coal gas.2)The best preparation conditions determined is shown as following: zinc, manganese and copper solution concentration of 20 %, 2 %, 6 % respectively; impregnated under pressure of 20 atm for 5 h, and calcined at 500 oC for 5 h.3)The breakthrough time of the best sorbent Z20M2C6SC was 95 h, with the sulfur capacity of 17.20 % and the precision of 0.1 ppm at 500 oC.4)It can be concluded that the improving of pore structure of semi-coke and the interaction between the active components are the main reasons influencing the sulfidation performance of sorbents.